In view of the high capital expense for scaling up power capacity to meet the escalating demand, maximizing the utilization of built capacity has become a top priority for multi-tenant data center operators, where many cloud providers house their physical servers. The traditional power provisioning guarantees a high availability, but is very costly and results in a significant capacity under-utilization. On the other hand, power oversubscription (i.e., deploying more servers than what the capacity allows) improves utilization but offers no availability guarantees due to the necessity of power reduction to handle the resulting power emergencies. Given these limitations, we propose a novel hybrid power provisioning approach, called $\mathsf {HyPP}$HyPP, which provides a combination of two different power availabilities to tenants: capacity with a very high availability (100 percent or nearly 100 percent), plus additional capacity with a medium availability that may be unavailable for up to a certain amount during each billing period. For $\mathsf {HyPP}$HyPP, we design an online algorithm for the operator to coordinate tenants’ power reduction at runtime when the tenants’ aggregate power demand exceeds the power capacities. Our algorithm aims at achieving long-term fairness in tenants’ power reduction (defined as the ratio of total actual power reduction by a tenant to its contracted reduction budget over a billing period). We analyze the theoretical performance of our online algorithm and derive a good competitive ratio in terms of fairness compared to the offline optimum. We also validate our algorithm through simulations under realistic settings.

中文翻译：

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用于多租户云数据中心应急处理的公平在线功率封顶

鉴于扩大电力容量以满足不断增长的需求的高资本支出，最大限度地利用已建容量已成为多租户数据中心运营商的首要任务，许多云提供商在其中安置他们的物理服务器。传统的电源供应保证了高可用性，但成本非常高，并导致显着的容量未充分利用。另一方面，电力超额订阅（即部署比容量允许的更多的服务器）提高了利用率，但由于需要降低电力以处理由此产生的电力紧急情况，因此无法提供可用性保证。鉴于这些限制，我们提出了一种新颖的混合电源供应方法，称为$\mathsf {HyPP}$高性能聚丙烯，它为租户提供了两种不同电源可用性的组合：具有非常高可用性（100% 或接近 100%）的容量，以及具有中等可用性的额外容量，这些容量可能无法用于 取决于每个计费周期内的一定金额。为了$\mathsf {HyPP}$高性能聚丙烯，我们为运营商设计了一种在线算法，当租户的总电力需求超过电力容量时，可以在运行时协调租户的电力减少。我们的算法旨在实现租户节电的长期公平性（定义为租户在一个计费周期内的实际总节电量与其合同节电预算的比率）。我们分析了我们的在线算法的理论性能，并与离线优化相比，在公平性方面得出了良好的竞争比率。我们还通过在现实环境下的模拟来验证我们的算法。